2 official rulings from Bandai, last ruled Nov 1, 2024. Straight answers to how this card actually resolves.

Can this card's inherited effect delete an opponent's [Sukamon] to prevent itself from being deleted?
Yes, you can.
Ruled Mar 28, 2024
I have [Sukamon] A and [Sukamon] B with this card in their digivolution cards in the battle area. When [Sukamon] A would be deleted, I attempted to delete [Sukamon] B using this card's inherited effect. On the other hand, when [Sukamon] B would be deleted, I attempted to delete [Sukamon] A using this card's inherited effect. At such times, can [Sukamon] A activate this card's inherited effect again?
No, it can't be activated. Until the processing for the 1st activation has resolved, only 1 activation is possible for each immediate-type effect. In your case, until the deletion of the 1st only [Sukamon] A is resolved, only 1 activation is possible for each "when [...] would" effect, therefore the effect that has already activated for [Sukamon] A can't be activated again.
Ruled Nov 1, 2024
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